Method of replacing valve seats



Dec. 22, 1931. w. s. PENFIELD METHOD OF REPLACING VALVE SEATS Filed March 5, 1928 2 Sheets-Sheet 1 elf 1 01 441 4.

Dec. 22, 1931. w. s. PENFIELD METHOD OF REPLACING VALVE SEATS Filed March 5.. 1928 2 Sheets-Sheet 2 gwum '(oz MMMMSPEA F/EAD Patented Dec. 22, 1931 UNITED STATES WILLIAM S. PEN'FIELD, OF SAN- FRANGISCO, CALIFORNIA METHOD OF REPLACING VALVE SEATS Application filed. March 5,

My invention relates to improvements in. methods of replacing valve seats, and 1t consists in the steps hereinafter set forth.

An object of my invention is to provide 5 a method of replacing valve seats which contemplates removing the worn valve seat and providing a wedge-shaped annular recess, the shorter diameter of the recess being at the top of the seat. Metal is now forced into the annular recess and entirely fills it, whereby the metal is provided with a wedge-shaped outer periphery that coacts with the wedgeshaped peripheral wall of the recess for preventing the removal of the metal. A new valve seat is now reamed into this. metal.

Heretofore it has been the practice to provide the recess with a vertical wall and then to force a ring into the recess, and depend upon friction to hold the ring in place. .With my improved method it is possible to force the metal into a wedge-shaped recess, whereby the contour of the recessed wall will hold the metal in place andmake it act as an 1ntegral part with the engine casting. Other objects and advantages will appear in the following specification, andthe novel features of my invention will be particularly pointed out in what I hereinafter claim.

My invention is illustrated in the accompanying drawings forming a part of this application, in which:

Figures 1 to 7, inclusive, show the different steps constituting the method.

In carrying out my invention it will be noted that the first step in my method is to cut out the old valve seat. Figure'l shows the valve seat 1 in full lines and indicates by dotted lines 2 how much metal is cut away by a standard cutter 8, in order to entirely re- 40 move the valve seat. Figure 2 shows the initial step of the method already completed. The old valve seat 1 has been removed and the circular recess 2 takes its place.

It is now necessary to taper the vertical Wall 4 of the recess. A tool 5, shown in Fig- 7 7 shows the new valve seat ready for receiving H 1928. Serial No. 259,325; ure 2, accomplishes this. This tool, like the tool 3, is of standard construction and therefore is shown by dotted lines.

Referring to Figure 3 it will be noted that x the recess 2 has been provided with a tapered or undercut wedge-shaped peripheral wall 6 and that a ring 7 has been placed upon a shoulder 8. A tool 9, of the shape shown in Figure 3, may be used for forcing and expanding the ring 7 into the recess 2. The ring is made of a metal strong enough to form the new valve seat. For clarity I have shown a tool 10 in Figure 4, in full lines, because this tool consists of a number of standard parts H that cooperatefor pressing the ring 7 against "6 the tapered wall 6.- The metal of the ring must be pliable'enough to permit this forcing action to take place. The tool 10 consists of a rotatable member 11 having a conicalshaped portion 12, and this portion bears against rollers 13, which in turn ride upon the inner periphery of the ring 7. The member 11 is forced downwardly and causes the rollers 13 to gradually move upwardly and V to squeeze the ring against the tapered wall "'70 6. This is a vital step in the process, and provides positive means for preventing the removal of the ring. It should also be noted that the roller 13 will press the inner portion M of the'rin'g 7 to a greater density than the remote portion. This will provide a greater resistance to the metal that is disposed adj acent to the valve seat, which will be cut in a manner presently to be described. We now come to Figure 5 and find that the upper surface 14 of the ring 7 must be ground down flush with the top 15 of the valve housing. A tool 16 of standard construction accomplishes this. The final step in the process is shown in Figure 6; Here, tool 17 is used for cutting a tapered valve seat 18. The seat is shown by the dotted lines in Figure 6, and is shown by the full lines in Figure 7 Figure a new valve.

I claim:

The herein-described method of making a new valve seat, which consists in cutting away the old valve seat, undercutting the peripheral Wall of the recess thus'formed for providing a smaller diameter at the top of the recess, forcing metal into the recess so as to conform With the undercut Wall, grinding down the top of the added metal flush with the top of the valve housing, and grinding a new valve seat in the metal.

WILLIAM S.- PENFIELD. 

